European Journal of Wood and Wood Products

, Volume 76, Issue 6, pp 1623–1636 | Cite as

The long-term evaluation of FRPs bonded to timber

  • Vahab ToufighEmail author
  • Mahdireza Yarigarravesh
  • Masood Mofid


This research investigated the long-term environmental effects on bond strength at the interface between fiber- reinforced polymers (FRPs) and timber. A total of 581 timber specimens were bonded with seven types of FRP sheets (unidirectional and bidirectional glass, carbon, aramid, and hybrids) using a wet lay-up technique. The specimens were exposed to acidic, alkaline, fresh water, and sea water solutions with pH of 2.5, 7, 7.25, 10, and 12.5 for 1, 3, 6, 9, and 12 months. A chamber was also used to simulate ultraviolet radiation after 6 months. A series of single-lap shear tests were then conducted to determine the interfacial bond strength reduction. The results showed that bidirectional carbon and glass FRP sheets demonstrated better bond strength as compared to unidirectional carbon and glass FRP sheets in most cases after exposure to the chemical solutions and ultraviolet radiation. Moreover, acidic and sea water solutions, respectively, had the most and the least effects on the reduction of bonds at the interface between hybrid FRPs and timber. Meanwhile, bidirectional aramid FRPs showed high deterioration in the interfacial bond strength under the effect of water and alkaline (pH 12.5) solutions. Finally, the failure modes on timber substrates were explored and classified.



This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.


  1. ASTM C581-15 (2015) Standard practice for determining chemical resistance of thermosetting resins used in glass-fiber-reinforced structures intended for liquid service. ASTM International, West ConshohockenGoogle Scholar
  2. ASTM D1141-98 (2013) Standard practice for the preparation of substitute ocean water. ASTM International, West ConshohockenGoogle Scholar
  3. ASTM D1583-01 (2013) Standard test method for hydrogen ion concentration of dry adhesive films. West Conshohocken, PAGoogle Scholar
  4. ASTM D3039-07 (2007) Standard test method for tensile properties of polymer matrix composite materials. ASTM International, West ConshohockenGoogle Scholar
  5. ASTM D3165–07 (2014) Standard test method for strength properties of adhesives in shear by tension loading of single-lap-joint laminated assemblies. West Conshohocken, PAGoogle Scholar
  6. ASTM D5266-13 (2013) Standard practice for estimating the percentage of wood failure in adhesive bonded joints. West Conshohocken, PAGoogle Scholar
  7. ASTMG53-96 (1996) Practice for operating light- and water-exposure apparatus (fluorescent UV-condensation type) for exposure of nonmetallic materials. West Conshohocken, PAGoogle Scholar
  8. Aydin H, Gravina R, Visintin P (2014) Effects of moisture, chlorides and sulphuric acid attack on CFRP to concrete bond interfaces. In: Proceedings 23rd Australasian Conference on the mechanics of structures and materials (ACMSM 23). Southern Cross Univ, Lismore, Australia, pp 409–414Google Scholar
  9. Aydin H, Gravina RJ, Visintin P (2016) Durability of adhesively bonded FRP-to-concrete joints. Journal of Composites for Construction 04016016Google Scholar
  10. Cai Z, Ross RJ (2010) Mechanical properties of wood-based composite materials. Wood handbook—wood as an engineering material. Forest Product Laboratory, MadisonGoogle Scholar
  11. CNR-DT 200 (2013) Guide for the design and construction of externally bonded FRP systems for strengthening existing structures. National Research Council, CNR-DT 200 R1/2013 RomeGoogle Scholar
  12. Cromwell JR, Harries KA, Shahrooz BM (2011) Environmental durability of externally bonded FRP materials intended for repair of concrete structures. Constr Build Mater 25(5):2525–2539CrossRefGoogle Scholar
  13. CSA (2004) Evaluation of adhesives for structural wood products (exterior exposure). CSA Standard O112.9-04, Canadian Standards Association, Mississauga, ONGoogle Scholar
  14. Custódio J, Broughton J, Cruz H (2009) A review of factors influencing the durability of structural bonded timber joints. Int J Adhes Adhes 29(2):173–185CrossRefGoogle Scholar
  15. Custódio J, Broughton J, Cruz H (2012) Rehabilitation of timber structures: novel test method to assess the durability of bondedin rod connections. Mater Struct 45(1–2):199–221CrossRefGoogle Scholar
  16. D’Ambrisi A, Focacci F, Luciano R (2014) Experimental investigation on flexural behavior of timber beams repaired with CFRP plates. Compos Struct 108:720–728CrossRefGoogle Scholar
  17. Gao WY, Teng JG, Dai JG (2012) Effect of temperature variation on the full-range behavior of FRP-to-concrete bonded joints. J Compos Constr 16(6):671–683CrossRefGoogle Scholar
  18. Gentry T (2011) Performance of glued-laminated timbers with FRP shear and flexural reinforcement. J Compos Constr 15(5):861–870CrossRefGoogle Scholar
  19. Ghiassi B, Marcari G, Oliveira D, Lourenço P (2013) Water degrading effects on the bond behavior in FRP-strengthened masonry. Compos Part B 54:11–19CrossRefGoogle Scholar
  20. Hassan SA, Gholami M, Ismail YS, Sam ARM (2015) Characteristics of concrete/CFRP bonding system under natural tropical climate. Constr Build Mater 77:297–306CrossRefGoogle Scholar
  21. Hong L, Duo RM, Wang SY, Li LX (2014) Influence of freeze-thaw cycles on bonded interface performance between CFRP and high strength concrete. Proc Appl Mech Mater 638:1516–1520Google Scholar
  22. Islam AA, Phillips D (2017) An experimental analysis of a timber Howe truss. Structures 10:39–48CrossRefGoogle Scholar
  23. ISO 13061-4 (2014) Wood—test methods for small clear wood specimens— Part 4: determination of modulus of elasticity in static bending. ISO (International Organization for Standardization)Google Scholar
  24. ISO 13061-7 (2014) Wood—test methods for small clear wood specimens—Part 7: determination of ultimate tensile stress perpendicular to grain. ISO (International Organization for Standardization)Google Scholar
  25. ISO 3132 (1975) Wood—testing in compression perpendicular to grain. ISO (International Organization for Standardization)Google Scholar
  26. ISO 3347 (1976) Wood—determination of ultimate shearing stress parallel to grain. ISO (International Organization for Standardization)Google Scholar
  27. ISO/DIS 13061-17 (2015) Wood—test methods for small clear wood specimens—Part 17: determination of ultimate stress in compression parallel to grain. ISO (International Organization for Standardization)Google Scholar
  28. Jiang X, Kolstein H, Bijlaard F, Qiang X (2014) Effects of hygrothermal aging on glass-fibre reinforced polymer laminates and adhesive of FRP composite bridge: moisture diffusion characteristics. Compos Part A Appl Sci Manuf 57:49–58CrossRefGoogle Scholar
  29. Joshaghani A, Ramezanianpour AA, Ataei O, Golroo A (2015) Optimizing pervious concrete pavement mixture design by using the Taguchi method. Constr Build Mater 101:317–325CrossRefGoogle Scholar
  30. Kabir MI, Shrestha R, Samali B (2012) Effects of temperature, relative humidity and outdoor environment on FRP-concrete bond. In: Proc, from materials to structures: advancement through innovation. CRC Press, LondonGoogle Scholar
  31. Lim JC, Ozbakkaloglu T (2013) Confinement model for FRP-confined high-strength concrete. J Compos Constr 18(4):04013058CrossRefGoogle Scholar
  32. Lopez-Anido R, Michael AP, Goodell B, Sandford TC (2004) Assessment of wood pile deterioration due to marine organisms. J Waterw Port Coast Ocean Eng 130(2):70–76CrossRefGoogle Scholar
  33. Lunn DS, Rizkalla SH (2009) Strengthening of infill masonry walls with FRP materials. J Compos Constr 15(2):206–214CrossRefGoogle Scholar
  34. Lyons JS, Ahmed MR (2005) Factors affecting the bond between polymer composites and wood. J Reinf Plast Compos 24(4):405–412CrossRefGoogle Scholar
  35. Maljaee H, Ghiassi B, Lourenço PB, Oliveira DV (2016) FRP–brick masonry bond degradation under hygrothermal conditions. Compos Struct 147:143–154CrossRefGoogle Scholar
  36. Meier U (1992) Carbon fiber reinforced polymers. Modern materials in bridge engineering. Struct Eng Int 2(1):7–12CrossRefGoogle Scholar
  37. Munafò P, Stazi F, Tassi C, Davì F (2015) Experimentation on historic timber trusses to identify repair techniques compliant with the original structural–constructive conception. Constr Build Mater 87:54–66CrossRefGoogle Scholar
  38. Raftery GM, Harte AM, Rodd PD (2009) Bond quality at the FRP– wood interface using wood-laminating adhesives. Int J Adhes Adhes 29(2):101–110CrossRefGoogle Scholar
  39. Richter K, Steiger R (2005) Thermal stability of wood–wood and wood–FRP bonding with polyurethane and epoxy adhesives. Adv Eng Mater 7(5):419–426CrossRefGoogle Scholar
  40. Saadatmanesh H, Tavakkolizade M, Mostofinejad D (2010) Environmental effects on mechanical properties of wet lay-up fiber-reinforced polymer. ACI Mater J 107(3):267Google Scholar
  41. Saracoglu E, Bergstrand S (2015) Continuous monitoring of a long-span cable-stayed timber bridge. J Civil Struct Health Monit 5(2):183–194CrossRefGoogle Scholar
  42. Schober KU, Harte AM, Kliger R, Jockwer R, Xu Q, Chen JF (2015) FRP reinforcement of timber structures. Constr Build Mater 97:106–118CrossRefGoogle Scholar
  43. Shen QR, Ran W, Cao ZH (2003) Mechanisms of nitrite accumulation occurring in soil nitrification. Chemosphere 50(6):747–753CrossRefGoogle Scholar
  44. Šilih S, Premrov M, Kravanja S (2005) Optimum design of plane timber trusses considering joint flexibility. Eng Struct 27(1):145–154CrossRefGoogle Scholar
  45. Tanyildizi H, Şahin M (2015) Application of Taguchi method for optimization of concrete strengthened with polymer after high temperature. Constr Build Mater 79:97–103CrossRefGoogle Scholar
  46. Toufigh V, Desai CS, Saadatmanesh H, Toufigh V, Ahmari S, Kabiri E (2013a) Constitutive modeling and testing of interface between backfill soil and fiber reinforced polymer (CFRP). Int J Geomech 14(3):671–681Google Scholar
  47. Toufigh V, Toufigh V, Saadatmanesh H (2013b) Behavior of FRP bonded to steel under freeze thaw cycles. Steel Compos Struct 14(1):41–55CrossRefGoogle Scholar
  48. Toufigh V, Ouria A, Desai C, Javid N, Toufigh V, Saadatmanesh H (2015) Interface behavior between carbon-fiber polymer and sand. J Test Eval 44(1):385–390Google Scholar
  49. Toufigh V, Yarigarravesh M, Mofid M (2017) Environmental effects on the bond at the interface of fiber reinforced polymer and Masonry brick. J Reinf Plast Compos 36(18):1355–1368CrossRefGoogle Scholar
  50. UNI EN 301-1 (2013) Adhesives for load-bearing timber structures-test methods-Part 1: determination of longitudinal tensile shear strength. German version, EN 302-1Google Scholar
  51. Wan J, Smith ST, Qiao P, Chen F (2013) Experimental investigation on FRP-to-timber bonded interfaces. J Compos Constr 18(3):4013006CrossRefGoogle Scholar
  52. Wang HT, Wu G, Wu ZS (2013) Effect of FRP configurations on the fatigue repair effectiveness of cracked steel plates. J Compos Constr 18(1):04013023CrossRefGoogle Scholar
  53. Yarigarravesh M, Toufigh V, Mofid M (2018) Environmental Effects on the Bond at the Interface between FRP and Wood. Eur J Wood Prod 76(1):163–174CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Civil EngineeringSharif University of TechnologyTehranIran

Personalised recommendations